Question

In C# in Windows 8, how can I pInvoke the IMetroMode::IsLauncherVisible method?

Details for the method are found here:
http://msdn.microsoft.com/en-us/library/windows/desktop/hh404166(v=vs.85).aspx

Answer 1

Use the IAppVisibility interface instead of the obsolete IMetroMode interface

Here is the sample code:

/* From ShObjIdl.idl
// CLSID_AppVisibility
[ uuid(7E5FE3D9-985F-4908-91F9-EE19F9FD1514)] coclass AppVisibility { interface IAppVisibility; }
 */
Type tIAppVisibility = Type.GetTypeFromCLSID(new Guid("7E5FE3D9-985F-4908-91F9-EE19F9FD1514"));
IAppVisibility appVisibility = (IAppVisibility)Activator.CreateInstance(tIAppVisibility);
bool launcherVisible;
if(HRESULT.S_OK == appVisibility.IsLauncherVisible(out launcherVisible)) {
    // Here you can use the launcherVisible flag
}

The IAppVisibility interface definition:

[ComImport, Guid("2246EA2D-CAEA-4444-A3C4-6DE827E44313"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
public interface IAppVisibility {
    HRESULT GetAppVisibilityOnMonitor([In] IntPtr hMonitor, [Out] out MONITOR_APP_VISIBILITY pMode);
    HRESULT IsLauncherVisible([Out] out bool pfVisible);
    HRESULT Advise([In] IAppVisibilityEvents pCallback, [Out] out int pdwCookie);
    HRESULT Unadvise([In] int dwCookie);
}
//...
public enum HRESULT : long {
    S_FALSE = 0x0001,
    S_OK = 0x0000,
    E_INVALIDARG = 0x80070057,
    E_OUTOFMEMORY = 0x8007000E
}
public enum MONITOR_APP_VISIBILITY {
    MAV_UNKNOWN = 0,         // The mode for the monitor is unknown
    MAV_NO_APP_VISIBLE = 1,
    MAV_APP_VISIBLE = 2
}
[ComImport, Guid("6584CE6B-7D82-49C2-89C9-C6BC02BA8C38"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
public interface IAppVisibilityEvents {
    HRESULT AppVisibilityOnMonitorChanged(
        [In] IntPtr hMonitor,
        [In] MONITOR_APP_VISIBILITY previousMode,
        [In] MONITOR_APP_VISIBILITY currentMode);

    HRESULT LauncherVisibilityChange([In] bool currentVisibleState);
}